Separator



Dec. 4, 1956 A. J. NERAD ET AL 2,772,749

SEPARATION Filed Dec. 16, 1953 Inventors: Anthony J. Nerad, "K Robert: Huohnson,

OIQF BrusdaJ, P by J. M

Thei'r- Att orn'ey.

United States Patentf) lice SEPARATOR Anthony J. Nerad, Alplaus, and Robert H. Johnson and Olaf Brusdal, Scotia, N. Y., assignors to General Electric Company, a corporation of New York Application December 16, 1953,Serial No. 398,502

2 Claims. (Cl. 183-36) This invention relates generally to separators and more particularly to centrifugal-separators for dust removal and air circulation which are primarily adaptedfor the purpose of separating dust, pollen, 'smoke'and similar particles from the air and for recirculating the air subsequent to the removal-of the particles therefrom.

Itis frequently desirable to incorporate with a separator an air circulator or fan for assisting in the disseparator nozzle of the conventional separator are elim- .inated.

In carrying out our invention in one form, dust laden air is drawn into the separator wherein the dust particles are separated and collected, and the clean air is recir-.

culated to the outside atmosphere by =an air circulator or fan.

These and various other objects, features and advantages of the invention will be better understood from the following description taken in connection with the accompanying drawing, in which the single figure is a vertical cross-section of a preferred embodiment of our invention applied to a centrifugal separator structure.

With more particular reference to the drawing, a separator is shown generally at which comprises a substantially cylindrical outer shell or casing 11 and an inner upwardly narrowing shell, liner, or sleeve 12 mounted coaxially within the outer shell 11. The outer shell 11 has an outwardly extending flange 13 at its lower edge. The inner shell is also provided wtih an outwardly extending flange 14 at its lower end and an outwardly ex tending lip at its uppermost end. A separating chamber 15, within which the entrained matter (which will be referred to as dust for conciseness) is separated centrifugally from the air or other gas, is defined by the shell portions 11 and 12. A top or upper wall structure 16 is seated against the upper end of the shell 11 and secured thereto by any suitable means, for example, by screws 17. An air inlet opening or aperture 18 is centrally disposed in the top Wall 16. An electric motor 19 is preferably secured at the marginal edge of the opening 18 and vertically spaced therefrom by means of suitable spacing elements 20 through which securing means such as for example, bolts 21 extend. The motor 19 has a shaft 22 projecting downwardly into the separating chamber on which is mounted a suitable cen- :age.

2 ,772,749 Fatented Dec. '4, 1956 trifugal blower impeller '23 having a plurality of curved blades 24. It "may "be seen from the drawing that the bottom surface of blower '23 and the lip end of sleeve '12 define an entrance contour for sleeve 12. It will be appreciated that the motor 19 is mounted substantially axially of the casing 11 and consequently the axis of rotation thereof is substantially coaxial with respect to the inlet opening 18. Consequently, the centrifugal action of the impeller blades 24 will serve to drive air coming in the inlet opening 18 downwardly and outwardly towards the outer wall-of the separating chamber and will impart a swirling action thereto. It will be noted that the air flow resulting from the swirling action generates -a vortex within the casing 11.

A cylindrical cap orbottom closure 25 is provided for the casing 11 and defines a dust-collecting chamber :26 therein. Thecylindrical cap 25 may be of any desired material and of any convenient depth to hold dust. The cap 25 may be retained-on the casing 11 by convenventional toggle clamps 27 fixed to the side wall of the cap -25 and removably secured on the flange 13 of the casing 11. An annular gasket 28 may be provided between the flange 13 and the cap 25 to prevent air leak- By the above construction, the cap 25 may be easily'removed to dispose of accumulated dirt. A centrally :dispose'd aperture '29 is provided in the bottom Wall of the the chamber defined by the shell 12 is in register with the aperture 29. A base 31, preferably extending par- :tially into .the aperture 29 to permit a radial discharge flow, may be provided for supporting the separator 10.

.A series of .supporting members 32 are provided about the upper surface of the base 31 for supporting the bottom "wall of the cap 25 on the base 31 and vertically :spa'cingithe cap 25 therefrom. Securing members, such as bolts 33, are provided through the base 31, the engaging member .32, the flange 14 and the bottom Wall aofitheicap 2'52and secured :by nuts 34. Each of the bolts '33 extends through -a continuous aperture as shown at In operation, the electric motor 19 serves, due to the centrifugal action of the impeller 23 above the separating chamber 15, to draw air axially inwardly through the opening 18 and impart a swirling velocity to this air around the outer wall 11 of the separating chamber 15. This air is driven helically downwardly through the separating chamber 15 to a point at about the upper level of the dust-collecting chamber 26. The centrifugal force of this swirling action tends to drive all of the solid particles towards the wall of the casing 11. These particles will then descend into the dust-collecting chamber 26. After the downwardly moving helical stream of air reaches a level approximately the top of the dust-collecting chamber 26 its direction is changed upwardly along the outer wall of the shell 12 in the center of the separator in a generally spiral path and then continues in a helical path substantially small in radius towards the upper end of the shell 12 While increasing in velocity due to the decreasing radius of the sleeve 12 and also undergoing expansion due to the upward flow into the lower pressure generater vortex. The air flow reverses its direction again and passes downwardly through the hollow shell 12 to the outside atmosphere. It will be noted that in this latter reversal any remaining particles in the air flow are given an outward movement in flowing over the lip of sleeve 12 and are entrained in the vortex flow for recirculation. These reversals of the axial direction of movement of the air is the natural path that the air must take in order to reach the outlet area at 29, and is eifected by the velocity imparted to it by the impeller 23.

The velocity of the air leaving the impeller blades 24 of the fan 23 is utilized directly in the centrifugal separator. The dust separator and the air circulator are thus made a single unit. The impeller is preferably designed so as to give just enough velocity to the air, such for example, 100 to 150 feet per second, for efiicient operation of the separator, and with enough pressure rise to overcome the small drop through the separator and to force the air through any exterior path necessary for a particular application. The velocity imparted to the air by the impeller is used in place of the conventional tangential nozzle in a separator. That is, the leaving velocity of the impeller is that which caused the centrifugal separation. The least efficient process in the air compression, that of diffusion, is eliminated because the air velocity at the tip of the impeller blades is used directly in the centrifugal separator.

From the foregoing, it is seen that the invention makes it possible to provide a dust separator having an air circulator employed therein whereby the dust laden air is separated, the dust collected, and the clean air recirculated to the atmosphere.

While the present invention has been described by reference to a particular embodiment thereof, it will be understood that numerous modifications may be made by those skilled in the art without actually departing from the invention. We, therefore, aim in the appended claims to cover all such equivalent variations as come within the true spirit and scope of the foregoing disclosure.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. A dust separator comprising in combination, a base, an annular dust chamber supported concentrically with and adjacent said base, a cylindrical casing coaxially supported by and in register with the upper opening in said dust chamber, a top wall structure on said cylindrical casing having an opening therein, a blower within the said casing adjacent the top wall structure opening and arranged to direct air entering through said opening in a vortical downward movement along the inner surface of said casing, and an upwardly narrowing diameter sleeve having a wide angle diverging lowermost portion, said sleeve being positioned coaxially within said casing with said lowermost portion in register with the annular dust chamber bottom opening, and an uppermost portion extending near said blower, the interior of said sleeve defining an air passage extending through said sleeve and radially outward between said sleeve and said base, whereby vortically downwardly moving air from said blower reverses near the lowermost portion of said sleeve and flows upwardly spirally about the said sleeve to again reverse and exit through said air passage.

2. A dust separator comprising in combination, a cylindrical casing having a top wall structure with an opening therein and an open lower end, a vortex generating blower within the casing adjacent said opening, an annular dust chamber surrounding the lowermost portion of said casing and having an upper opening in register with said open lower end of said casing, an upwardly narowing diameter sleeve positioned concentrically within said dust chamber and said casing and having its largest diameter portion in register with the lower opening of said dust chamber, the narrowest diameter portion extending upwardly near said blower, said sleeve constituting the sole exit from said combined casing and dust chamber, a supporting base in spaced relationship with said dust chamber and defining an internal and radial air passage with said sleeve, said blower forming a vortical parttern of air which moves downwardly along the inner surface of said casing, the combined narrowing diameter sleeve and the low pressure of the vortex causing the downward moving air to reverse about said sleeve, the said upwardly narrowing diameter sleeve defining a flow path for the said reversed air, the said air reversing again at the uppermost end of said sleeve to exit downwardly therethrough.

References Cited in the file of this patent UNITED STATES PATENTS 1,230,827 Duflie June 19, 1917 1,480,775 Marien Jan. 15, 1924 1,743,344 Hawley Ian. 14, 1930 1,874,061 Redfield Aug. 30, 1932 2,143,144 'Fagerberg Jan. 10, 1939 2,375,203 Appeldoorn May 8, 1945 2,462,797 Whittaker Feb. 22, 1949 FOREIGN PATENTS 62,730 Germany June 11, 1892 609,093 France May 3, 1926 

